Objective. To evaluate the significance of therapeutic drug monitoring of adalimumab (ADA) concentration levels and antibodies to it in inflammatory bowel disease (IBD) in children. Patients and methods. In this study, 103 children with IBD (24 patients with ulcerative colitis (UC) and 79 with Crohn’s disease (CD)) aged 3–18 years were examined during maintenance therapy with ADA (100 mg/mL in 0.4 mL). Body weight, duration of disease and therapy, use of azathioprine (AZA), achievement of clinical and endoscopic remission, albumin levels, residual levels of ADA and antibodies to the drug, circulating cytokine levels in serum were assessed. Results. A significant decrease in ADA levels in children in the absence of clinical remission in CD (5.21 [3.32; 7.43] μg/mL in remission) and in UC (2.42 [0.42; 4.51] μg/mL, p = 0.001) was shown. A high-quality separation model for residual ADA levels for exacerbation/remission conditions for clinical and endoscopic activity for children with CD and UC was obtained through ROC-analysis. The minimum residual ADA levels for maintaining clinical remission in children with CD were 8.1 μg/mL and 10.5 μg/mL for mucosal healing. In children with UC, as well as in children weighing <40 kg, these levels were higher. The formation of antibodies to ADA was minimal; combination therapy with AZA showed no efficacy. Key cytokines correlating with ADA concentration were interleukins IL-6, -13, -31, -27, -9, and tumor necrosis factor-α. Conclusion. To improve the efficacy of ADA therapy in children with IBD, therapeutic drug monitoring should be performed, considering the nosology and body weight of the child, as well as the goal of therapy (clinical and endoscopic remission). Key words: inflammatory bowel disease, Crohn’s disease, ulcerative colitis, adalimumab, therapeutic drug monitoring, tumor necrosis factor-α, cytokine profile, azathioprine
Therapeutic Drug Monitoring During Induction of Anti–Tumor Necrosis Factor Therapy in Inflammatory Bowel Disease
